Ferromagnetism induced in rutile single crystals by argon and nitrogen implantation

Abstract

The magnetic properties of Ar- and N-implanted single crystalline TiO(2) rutile were studied and correlated with the induced disorder in order to clarify the influence of defects in the magnetic behaviour. Nominal fluences of 1 × 10(17) and 2 × 10(17) cm(-2) and an implantation energy of 100 keV were used. The as-implanted single crystals exhibited ferromagnetic behaviour up to 380 K. Annealing at 1073 K induced recovery of the lattice structure and the decrease of the ferromagnetic moment in the case of Ar-implanted samples, but the magnetic moment did not change significantly for the samples implanted with nitrogen. No impurities, other than the implanted species were detected and consequently the ferromagnetic behaviour is attributed to defects created during implantation, which in the case of nitrogen remained in the lattice even after partial recovery of the structure.